why am I bleeding for so long!

ok hi I’ve been on alysena since October and usually my bleeds last 4 days , I started my placebo pill on sunday and started bleeding wednesday… it usually is a two day heavy bleed then it just stops completely and I see some spotting for the next day. it’s been 4 DAYS and I’m still heavy bleeding + slightly cramping :-( is this normal ? I haven’t missed any pills and take my pills at the same time on the dot every single day. my new pack starts today so I’m hoping that it lessens but it is so annoying and I’m confused because it hasn’t been like this at all